The best way to get better, as cheesy as it is, is just to play. I always try and user Shazier, and have him in a yellow zone covering the center of the field. Intuition on what your opponent is going to run helps, and you’ll build that as you play. Your defense should bend, not break, so be willing to give up small completions to take away big gains if you have to choose between two receivers to guard. As you play, you’ll begin to be able to judge how far away you can be from a route and still get there in time to swat/pick so you can bait your opponent to throwing to the receiver you want him to. Tfribourg69 also has some good tips as well^